Slashdot Mirror
Google Pulls Support For CDMA Devices
An anonymous reader writes "Google has just made some interesting changes to their developer pages. As of today, all of the documentation, source code, and firmware images pertaining to CDMA Android devices (including the Verizon Galaxy Nexus) have been removed. A statement from Google explains that the proprietary software required to make these devices fully functional got in the way of Android's open source nature, so CDMA devices are no longer supported as developer hardware. What does this mean for the Galaxy Nexus, which is only available as CDMA in the U.S.?"
Sounds to me like the carriers and Google butted heads on some code, and this is Google putting the pressure on the carriers to open up parts of their software, but that is purely speculation on my part. I'm just curious how this is going to play out with Sprint's rollout of the LTE Google Nexus.
It's used in the US, where they are 20 years behind the rest of the world in mobile phones.
Come on, America, at least move onto GSM. Now that it's all being ripped out and replaced with 3G there's a lot of GSM hardware on the second-hand market. It's not even expensive.
Make things easy on yourselves. Take that giant leap into the year 2000.
The Galaxy Nexus will continue to work just fine on CDMA. For future models, well, that's another story... Google forces the industry to either open up their firmware or move on to GSM. Good thing, IMO.
Come on, America, at least move onto GSM. ... Take that giant leap into the year 2000.
What are you talking about? GSM has been available in the U.S. since before 2000. It's not our fault some carriers hold onto CDMA. But really, you can't blame them when it worked perfectly well for their purposes. Me, I think a lot of it was to make it more difficult for people to use second-hand phones, since you can't just swap your service from one phone to another on your own like you can GSM.
The GSM standards as originally developed were deliberately chosen to work on bands (900 MHz , IIRC) that in the US were assigned to the military. That is, to be initially incompatible and unusable in the US, so as to split the world into "US" and "rest", and give non-US developers a head start. It worked ...
Anyone who believes exponential growth can go on forever in a finite world is either a madman or an economist
And only for some features. Consumer phones will of course still be fully supported, receive all updates etc.
AOSP builds from source have never had full telephony function for CDMA devices due to missing carrier binaries, so Google is moving to clarify this, and is no longer listing CDMA devices as fully supported for developers.
Why would anyone engrave "Elbereth"?
Except that East Asian deployments of CDMA2000 use SIM for network authentication - changing phones in Japan, Korea, or India is as simple as moving a little smartcard around. Just like in GSM. Don't hold me to it, but it might also apply to CDMA2000 networks in Eastern Europe.
Only in the Americas do CDMA2000 networks still use MEID for authentication, as far as I know.
I know that CDMA is an older standard, however, from what I remember it has always had better voice quality and tower transfers than GSM.
The one big advantage of GSM is the use of SIM cards, and that simultaneous voice and data were possible. CDMA also has better spectral efficiency than TDMA used by GSM. Check out Wikipedia's article on it and look at the efficiency of the latest CDMA vs GSM standard.
Don't act like the carriers stuck with CDMA to be dinosaurs. It actually was , at least for voice users, the better technology.
In Japan, they also have W-CDMA (UMTS), but at least the phones there typically use uSIM cards, which just happen to be similar to GSM SIM cards.
I can take any unlocked phone that supports UMTS, and put in any uSIM card from any other the 3 major carriers (softbank, au, & docomo) and it will work.
However in the USA, CMDA based carriers refused to allow any type of uSIM support for their networks, since they want users to be locked down to their networks. Even if you paid the extra $$$ for an unlocked iPhone 4S, you cannot get it work on both Sprint and Verizon the networks. The iPhone unlock is only for GSM not CDMA in the USA. The same is also true for Android phones as well.
I am very happy to see Google finally stand up against the horrible CMDA situation in the USA. As previous commenters have stated, it would be nice if either CMDA went away, or they followed the example of Japan, and are required to have uSIM cards.
The goal should be to have every unlocked smart-phone unlocked and able to work with every carrier, but simply inserting a SIM/uSIM card. Personally I think it is horrible that smart-phones are not required to be unlocked, since these phones are typically not subsidized with 2-3 year contacts that covers the full cost of the phone many times over.
Only in the Americas do CDMA2000 networks still use MEID for authentication, as far as I know.
So... you're agreeing with me then? Yes, perhaps there are some versions of CDMA that have the flexibility of SIMs, but that's not what the U.S. carriers deployed. That still jives with my idea the choice was entirely deliberate to help carriers maintain control of hardware (and customers) and boost contract re-ups, etc.
It's just another method of creating artificial business barriers in an increasingly small world. Like region encoding DVDs and the U.S. adopting ATSC for HD broadcasting instead of using DVB-T or ISDB.
3G just means 3rd generation. So while W-CDMA is a 3rd generation network technology, it does not mean that all 3rd generation technology is W-CDMA.
Google is just handing over Verizon's & Sprint's customer bases over to Apple, Microsoft and others?
Good Thing you added a question mark because this doesn't mean Google is handing anything over to anyone. Google and Carriers are still more then welcome to use CDMA technology all they like and are free to do anything they want with the phones as long as all the licensing requirements of all the software they use are met. Google removing CDMA from the developer pages is not the same thing as Google saying that the android license and therefor anyone using the android software is now restricted from using CDMA and it can no longer be used because that is not what it means. It means Google is having issues complying with certain licenses by posting the CDMA specs online and therefor they have simply taken it out of the open space where anyone in the world is now able to access it but carriers like Verizon and Sprint and Manufacturers like Samsung, HTC, LG, etc, etc will have no problem obtaining the resources and permissions to develop and implement the CDMA functionality and I'm willing to bet that Google will not only make it easy to load this functionality in a modular way which will ease integration but I also bet that will be aiding with the design and development to these companies to make sure it's done. Don't misinterpret Google taking CDMA from the open developer pages as meaning anything even close to saying Google is not going to allow CDMA on Android phones anymore because one example I can think of already is Sprint, a CDMA provider, has the contract to deploy Galaxy Nexus phones as soon as the exclusivity rights for Verizon finish. People shouldn't jump to conclusions so quickly based on a gross over simplification of what is actually being said without taken a moment to read it thoroughly and make an effort to understand the real implications of the actions. Hope this answers your question.
Google isn't "Dropping" CDMA support. CDMA Android phones aren't going anywhere any time soon - they're just not supporting them as DEVELOPER devices. Due to issues with Custom ROMs not working as best they could (due to the proprietary components required), Google is basically saying that the CDMA Nexus phones are no better than any other non-nexus device when it comes to "official" developer support. They'll still exist, they'll still be sold, updated, etc. but they won't be classed as "Developer devices". That's it.
This isn't anything new, it was the same case with the Nexus S 4G and even the Xoom.
+1 IDisagreeSoHeMustBeATrollOrAnAstroturferOrAShill
Storing contact info on the SIM is best treated as a secondary, legacy function. For any more complicated set of personal data you're better off exporting it in some standard-ish format your new phone can handle, or syncing it via some external service. Also, at least all the HTC Android phones I've seen seem to have no difficulty pulling the data from other devices via Bluetooth.
Being able to switch providers or phones by moving SIMs is worth even inputting the contact data manually, imo.
GSM has a fixed maximum cell size - 20km radius at first, later extended to 35km. CDMA doesn't have a maximum. GSM does because it uses time division multiplexing - several phones can transmit and receive on the same frequency, and they take turns. The further from the tower your phone is, the longer the signal takes to travel back and forth, and there comes a point where your transmissions spill into the next slot, reducing call quality for whoever's using it. If you get to that distance from the tower, it will just drop the call. The maximum cell size is a tradeoff between how much equipment the network needs to serve a given area and how much spectrum it would have to use.
In densely-populated places like most of Europe, the maximum cell size isn't really an issue - there aren't many places where you can leave one settlement and travel 20km without entering another. Australia and North America, on the other hand, are much more spread out, and the number of GSM cells that would be needed to provide acceptable coverage to rural areas would be too expensive for the likely revenue from them.
Just another wannabe fantasy novelist...
Actually, I work in a lab that programs, tests, and services phones on all four carriers. You are absolutely correct in your statement! Sprint and Verizon both were using CDMA for that reason. Verizon has now switched to LTE for quite a bit of it's network but Sprint is still using a combination of CDMA and WiMax. While AT&T and T-Mobile were using GSM but have now mostly switched to HSDPA(HSPA+) and LTE respectively.
What most people don't realize is that none of the technologies that are currently out can truly be called 4G! Unlike 3G, there is no specific standard for what is considered 4G service yet. The industry is saying that these specifications are in development, but right now 4G is more of a gimmick to get consumers to buy the latest and greatest thing! 2G service came out around 1995, 3G came out around 2005. Mobile infrastructures, in the USA at least, seem to be on a ten year cycle. With that said there most likely will not be a "4G standard" till around 2015. Sprint actually has the most right to call it's network 4G, not because of speed, but because it is the 4th generation of it's network.
I love ignorant fools opening their mouths. They make asses of themselves and don't even realize it.
You are aware that CDMA is technologically superiour to GSM in EVERY way. In fact, CDMA is most comparable to WCDMA/UMTS, as they're both 3G technologies and WCDMA/UMTS in fact borrowed heavily from CDMA for their air interface. GSM is the most widly deployed network architecture, true, but don't think for a second it's because it's superior. It's because it's cheap. Period.
The USA was the first to roll out 2G, half went with CDMA, half went with GSM. The GSM crowd because it was an international standard, and the CDMA crowd because it was far superior to GSM, and cost wasn't that different because GSM had yet to have wide spread deployment to drive cost down. As time went on though, since CDMA is heavily patented by Qualcomm, it meant the price stayed high when the rest of the world started rolling out their networks, so they went with the cheaper GSM.
I also have a theory that part of GSMs adoption in europe is due to a very "europe first" mentality, and due to strong american ties to CDMA, they didn't want to go that way, but again, just a theory on my part, and the cost probably was the bigger motivator.
Lastly, CDMA as deployed in the USA is a 3G technology, why ditch it for a 2G network? At least tell us to ditch it and go with UMTS. Oh, and the US also has every one of those technologies deployed. AT&T and T-Mobile are GSM/UMTS networks, Verizon and Sprint are CDMA networks. And everybody seems to be heading to LTE for 4G networks.
-A cellular network R&D engineer.
According to Wikipedia (and its cited sources), the 4G spec was finalized in 2008, and would require the ability for sustained data rates of 100Mbps. Current networks don't meet that, but LTE-Advanced could, and is only a firmware upgrade removed from current LTE systems.
Links: http://en.wikipedia.org/wiki/4G#Requirements and http://en.wikipedia.org/wiki/IMT_Advanced
Sig? What's that? Oh, 'signature'...and it's supposed to be witty? Right...
It doesn't forbid it, as I recall. It makes it optional and virtually every carrier opted not to as it gives them more control over the handsets.
CDMA was the first technology to enable "reuse 1" deployment.
In a GSM network, you need to use several frequencies to deploy one layer of the network, so that a cell doesn't interfere with a close cell. Using 7 frequencies for example allows a cell and all its immediate neighbor cells (using an hexagonal paving) to have different frequencies. Then the the closest cell with the same frequency is not adjacent but one hop further, and its interference is reduced.
In a CDMA network, all cells in a layer can use the same frequency. Now a mobile close to its cell where the signal is high is fine, but a mobile far from its cell and hence close to another neighbor cell will suffer interference. But this can be mitigated. In CDMA the bandwidth is split between codes, and neighbor can share the code space without trampling on each other feet and creating undue interference. There's still interference at the edge, and for a give frequency the cell capacity is lower than in GSM. But now you could use the 7 frequencies of GSM to provide 7 layers instead of a single one. And you gain in total capacity. In other words, reuse 1 reduce the capacity for a single frequency, but allows maximizing the usage of each frequency, and maximizing the network capacity. That's what got every operator so excited.
This being said, CDMA as deployed in CDMA2000/EVDO networks is now pretty backward and expansive. That's why all US CDMA operators are so eager to move to LTE and leave it behind. HSPA+ is much better, and what is amusing is that it kind of move away from the CDMA tenets to introduce back TDM principles (GSM is TDM based). HSPA+ is still CDMA based, but instead of transmitting over a few codes for a long time (as initially done with CDMA), it transmits for a short duration and use most codes. And multiplexing is done over time (as in TDM). Because it turns out that this is most efficient.
Anyway, you can safely ignore fanboys of either GSM or CDMA. It's our past. The future is now and is OFDMA, as used first by WiMAX and now LTE. It also allows for reuse 1 deployments, but instead of handling allocation based on time only (GSM), or on time and codes (CDMA), it handles allocations based on frequency and time. The bandwidth is split in many small carriers (15 kHz spacing in LTE for example). Carriers are groups in bunches (a resource block in LTE is 12 carriers for example). And you allocate several RBs to a device for a subframe of 1 ms. Allocation can change each subframe.
What's the gain of OFDMA? Better handling of multipath. When you're cell phone receive the signal from the base station, it actually receives a "main path" and several echoes due to reflexions on buildings, etc. Also, the higher the bandwidth the shortest the elementary symbol duration. At some point, a symbol becomes mixed with echoes from other symbols and decoding becomes a mess. With OFDMA, become each channel is low bandwitdh (15 kHz, compared to 5 MHz for 3G for example) the symbol duration is very long. There's no problem handling with echoes, become the time delay is very small compared to the OFDM symbol duration. The price to pay for this is doing a FFT over the bandwidth to recover all the basic carriers. That's up to 2k FFT. It's doable and practical now thanks to Moore law.
That should give you a quick overview. And to the experts: please forgive the necessary simplifications to fit in a few paragraphs.